Coupling



May 12, 1953 J. A. JONES COUPLING Filed Aug. 4, 1949 INVENTOR. JOHN A. JONES Patented May 12, 1953 vpi'esent:inventiomrelatesr tosan. improved-ill within.. .these.lsteps' are shafitleoupling-or clamping mechanismufonclampa inga'pul-leys gear anditherlike ito a..-shaft;

Theleprincipallmobiectsof Zthe. inventiom is. ton: provide ::a clarnpi-Zflgalzneansdfors ;collairs; .pullys,m or.mother.driyingnor driven ..elements,-. whichhis-e adaptedio... engage a .cylindrical.surfaeawithout. i the; necessity of" scoring on=penetrating..the..sure fatzanfdtheashaft. as is..the. case awheniusing a settscrew 012a key-Way, p I

Anothenobject of thtinvention. iatogprovide'... such.Lan article ori device whichlmay.joeneasilyg and conveniently attached to, or detachedairom,:.

the.shaft. v I

tillifanother.objectpfuthennvention isito' pro vide..a structure.zforiisucmaniarticle that..will..be..; economical tmconstruct.andeifidientin..its .operel ation.

Withith'esel anduother objects in view, the invention consists of the novel construction, combinatiemand arramglement of parts aslshewncin the accompanying. drawings, and described in the written detailed description forming a 'part' of this specification, in which? Figured Es a horizontal sectionalviewmf tlie couplings Figure 2 is a sectional View taken along the I line 2-2 of Figure 1.

Figure 3 is a sectional view taken along the line 3-3 of'Figure 1.

Figure 4 is a plan view of the clamping element.

Figure 5 is a horizontal sectional exploded view of the coupling housing.

Figure 6 is a view partly in elevation and partly in section of a driving element associated with the coupling.

In referring to the detail description of the article, the term coupling is used in its broad sense to indicate a means for holding an element in contact with a shaft such as a collar, the hub of a pulley, gears, and similar driving, or driven, elements. It is also intended to include any type of coupling between two shafts or machine parts where an element is to be secured to a cylindrical surface.

In pointing out the invention, like reference characters are used to indicate like and similar parts throughout the several views when practical to do so.

Referring more particularly to the construction of the coupling, there is provided a housing having a body member [2 with a cylindrical opening therein. This member I2 is formed with steps [2' and I2" at its opposite ends. Fitting ban 2 El 1 which .is adapted .to'-fit..snngly. withirnt -oLitolerancehwh-icn. .will-inkeepmthe couplin endabearing. unember ial L and; 'I 5., Cut her-mentallyqwithinlthe..pontionfl 212 isia -kewway ,l 8,.and fitted-within.the.cylindricalli opening otathelpertioml 2 is.a.spiralldcoilinemai cylindricattopening. Thermemberi 20 extends ll. substantially.,the=:-full length bathe couplingba. tween .the--end. members...l t andil 6L The-spiral member 28 ;is- =coi-ld in. opposite directionsifromnits center, and the inside .diameter..-0f-.=the-coil.)

is normally slightly larger than-.the. bearing-.surfaces. l4 ands! 6.? in-mdenthat-theficouplingiwillw slipqe'asilylsover the shaft. Thesexbearingesura faces are-adaptedto-fittheshaft withla min um.

alignment regardlessrofithel position the grippmgs elemenal flumaygtakex: I

In "leifectingiagripping tactionson ...th-e-- shattgl P. there-aisupreterably provideci -1neansateach-endm ofttherspiral to move thaends. circumterentiallyn within .thezrhousingaand.:in thensame direction.- while'tha centenotthelspiral ismoved iii-the ope posite directions,

While; beth ends. 10f the spiralled coiluand the h centen ipontionmare preferablyismovedv-to eobtainl the grippingmctioneupon theishatt; itlisinot nec+ essary, only in instances where an exceptional gripping action is needed, and the tightening action may only be applied either at the ends or at the center, the ends or center being fixedly held within the key-way l8.

In order to give the spiral the gripping action, there is provided a set-screw 22 at each end of the housing (only one being shown) which is carried within a threaded aperture within the housing, and a set-screw 24 similarly mounted within the housing for contacting the center portion 28' of the coil. As stated hereinbefore, the end set-screws move the coil in the same direction, and the centrally located set-screw moves the coil in the opposite direction.

In manufacturing the coupling, the housing member I2 is preferably made of a tubing having the proper thickness and the proper cylindrical diameter. The tube is cut to proper length and the steps l2 and I2 are cut at each end thereof. Along the face of the cylinder is a slot [8 of a predetermined width. At each end of the housing there are end members I 4 and I6 which are made separately and of such dimensions as to be pressed into the steps l2 and 12" of the member 12. The surfaces l4 and [6 of the end pieces are adapted to fit closely the shaft upon which the coupling is to be used. The coiled member 20 is formed to be carried within the cylindrical surface of the member l2 and the end members. The inner diameter of the coil is normally substantially that of the bearing surfaces l4 and Hi. In this particular disclosure, the ends and a portion of the center section are turned outwardly to engage the slot I8. Opposite the location of the out-turned ends within the slot I8 is a threaded aperture 23 for receiving the screw 22. The set-screw 22 is located on the side of the slot 18 to exert pressure on the upturned end of the coil in the direction of the spiral, as shown in Figure 2, which will cause the inside diameter to be reduced upon moving the screw inwardly. The structure and aperture of a corresponding set-screw at the opposite end of the coil is substantially the same. Adjacent the center of the coil at 20' is a single screw 24 positioned on the opposite side of the slot I 8 and is adapted to contact the loop portion of the coil at 20' for moving the center of the coil in the opposite direction. After the coupling has been assembled, the pressure screws are backed off to a predetermined point and the inner circumference of the coil ground to the size of the shaft after which the coil can be fastened to the shaft by tightening down on the screws. By using the double acting coil and the set-screws as described, an exceptional gripping action may be gotten on a shaft without defacing the shaft in the slightest degree.

While the coil member 20 is shown having two coils on each side of the center loop 20', it may be either a single coil or have any number in excess of two if the circumstances call for it, and while the coil has been described as having means at both ends and at the center for exerting pressure on the spiralled coil, it is not necessary in certain cases when extreme pressures are not required. In this case, either the end pressure means, or the center means, may be eliminated, and these respective points of the coil may be held within the slot 18 while either the end or center pressure means is operated.

In operation, the coupling is adapted for use where the use of set-screws and key-ways in the 4 shaft member is objectionable, and/or where it is necessary to make slight adjustment between the shaft and the coupling. For example, the coupling may be used to secure a timing gear 30 to a shaft, as illustrated in Figure 6, or any other element such as a pulley, collar, or the like.

While the invention has been shown and described in a particular form, it is not intended in any way to be a limitation as various changes may be made without departing from the spirit of the invention, and the scope of the invention is best defined in the appending claims.

I claim:

1. A shaft coupling of the class described comprising a continuous housing unit having an opening extending through the said housing, the outer end portions of which are of cylindrical form for slidably receiving a cylindrical shaft and a single internal recess formed in the housing between the cylindrical end portions, a single coiled helical gripping element carried within the recess and extending between the outer end portions having its normal inner diameter slightly larger than the cylindrical openings in the end portions, the said gripping element extending in opposite directions from a point adjacent its center, means for preventing the movement of the central portion of the gripping element against movement in the direction of the winding of the helix and means carried by the said housing adjacent the ends of the recess for operating the gripping element in the direction of the helix beyond its normal position for gripping the said shaft.

2. In a device as set forth in claim 1 having means for moving the central portion of the coiled helical gripping element in the opposite direction of the winding of the helix.

JOHN A. JONES.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 631,956 Diescher Aug. 29, 1899 701,017 Diescher May 27, 1902 

